Chiropractic tables are known for use in treating patients suffering from a variety of orthopedic and neuropathic maladies. Such treatments include placing the patient's spine in vertical flexion (head to chest motion), extension (head to back motion), lateral flexion (left and right motion) and rotation (turning motion), as well as coupling vertical and lateral flexion to produce circumduction. Chiropractic tables are described in U.S. Pat. No. 4,050,454 of Ekholm, U.S. Pat. No. 4,230,100 of Moon, U.S. Pat. No. 4,245,626 of Paolino, U.S. Pat. No. 4,314,552 of Moon, U.S. Pat. No. 4,523,581 of Ekholm, U.S. Pat. No. 4,649,905 of Barnes, U.S. Pat. No. 5,794,286 of Scott et al., U.S. Pat. No. 5,954,750 of Steffensmeier and U.S. Pat. No. 6,679,905 of Peetros, et al. Chiropractic tables commonly include one or more sections, some or all of which may include a drop mechanism for use in treating a particular portion of the patient's body. Generally, these drop mechanisms include an actuating mechanism that allows the table section, or a portion of the table section, to move abruptly and rapidly through a controlled distance when a force or pressure is applied to a body part that is supported on the table section by a chiropractor or other therapist. It is common for a chiropractor or other therapist to employ a series of drop treatments in succession in order to provide a therapeutic benefit. Consequently, a mechanism must be provided to raise the drop section of the table back up to its “pre-drop” level after each drop treatment. Some chiropractic tables are provided with a manually-operated “cocking” device to raise the drop section by using a hand lever to rotate a cocking shaft that is connected to the drop section. However, a disadvantage of such mechanisms is that they are time-consuming to operate and require considerable effort on the part of the practitioner, particularly if the patient is heavy. Other tables include a cocking device which includes a fluid actuator that is employed to raise the drop section. However, these actuators tend to raise the drop section rather quickly, and some patients find this uncomfortable and/or disconcerting. U.S. Pat. No. 4,245,626 of Paolino describes a table which includes a motorized cocking device in which an electric motor, a speed reducing gear train and an eccentric linkage assembly are employed to rotate a cocking shaft to raise the drop section. Although this motorized cocking device is reported to provide a “gentle cocking action which will not injure or alarm the patient”, it does require a complicated and expensive assembly of components.
It would be desirable, therefore, if a therapeutic device could be developed for providing a controlled cocking action to raise the drop section at a rate that is comfortable for the patient. It would also be desirable if such a device could be provided utilizing reliable and inexpensive components.